Sequence variability, recombination analysis, and specific detection of the W strain of Plum pox virus

Miroslav Glasa (1) , Tadeusz Malinowski (2) , Lukáš Predajňa (1) , Neda Pupola (3) , Dzintra Dekena (4) , Lech Michalczuk (2) , Thierry T. Candresse (5)

1 SAS - Slovak Academy of Sciences
2 Research Institute of Pomology and Floriculture
3 State Institute of Fruit-Growing
4 Pure Horticultural Research Centre
5 BFP - Biologie du fruit et pathologie

Plum pox virus (PPV), a member of the genus Potyvirus, is the causal agent of Sharka, the most detrimental disease of stone-fruit trees worldwide. PPV isolates are grouped into seven distinct strains. The minor PPV-W strain was established recently for the divergent W3174 isolate found in Canada. Here, the partial or complete genomic sequences of four PPV-W isolates from Latvia have been determined. The completely sequenced isolates LV-141pl and LV-145bt share 93.1 and 92.1% nucleotide identity, respectively, with isolate W3174, with two regions of higher (>20%) divergence in the P1/HC-Pro and NIa (VPg) regions. Further analyses demonstrated that these two regions correspond to two independent recombination events in the W3174 genome, one involving PPV-M (approximate genome positions 692 to 1424) and the other PPV-D (nucleotides 5672 to 5789). The LV-141pl and LV-145bt isolates appear to be representatives of the “ancestral” PPV-W strain, not affected by recombination. The PPV-W intrastrain variability is substantially higher than that of all other PPV strains, with potential implications for the serological detection of PPV-W isolates. A PPV-W-specific primer pair has been developed, allowing the specific reverse-transcription polymerase chain reaction detection of all five presently available W isolates. The characterization of these new PPV-W isolates sheds light on PPV-W evolutionary history, further supports the hypothesis of its East-European origin, and opens the way for the biological and epidemiological characterization of this poorly known PPV strain.

Mots clés: winona; isolat; diversity; nucleotide sequence; sharka disease; rna viruses; potyvirus; isolate

Mots clés: virologie; coat protein; ppv; populations; evolution; dna

Domaines: Phytopathologie et phytopharmacie

Miroslav Glasa, Tadeusz Malinowski, Lukáš Predajňa, Neda Pupola, Dzintra Dekena, et al.. Sequence variability, recombination analysis, and specific detection of the W strain of Plum pox virus. Phytopathology, 2011, 101 (8), pp.980-985. ⟨10.1094/PHYTO-12-10-0334⟩. ⟨hal-02647282⟩